xref: /openbmc/u-boot/arch/arm/mach-socfpga/fpga_manager.c (revision d024236e5a31a2b4b82cbcc98b31b8170fc88d28)
1 /*
2  * Copyright (C) 2012 Altera Corporation <www.altera.com>
3  * All rights reserved.
4  *
5  * This file contains only support functions used also by the SoCFPGA
6  * platform code, the real meat is located in drivers/fpga/socfpga.c .
7  *
8  * SPDX-License-Identifier:	BSD-3-Clause
9  */
10 
11 #include <common.h>
12 #include <asm/io.h>
13 #include <linux/errno.h>
14 #include <asm/arch/fpga_manager.h>
15 #include <asm/arch/reset_manager.h>
16 #include <asm/arch/system_manager.h>
17 
18 /* Timeout count */
19 #define FPGA_TIMEOUT_CNT		0x1000000
20 
21 static struct socfpga_fpga_manager *fpgamgr_regs =
22 	(struct socfpga_fpga_manager *)SOCFPGA_FPGAMGRREGS_ADDRESS;
23 
24 /* Check whether FPGA Init_Done signal is high */
25 static int is_fpgamgr_initdone_high(void)
26 {
27 	unsigned long val;
28 
29 	val = readl(&fpgamgr_regs->gpio_ext_porta);
30 	return val & FPGAMGRREGS_MON_GPIO_EXT_PORTA_ID_MASK;
31 }
32 
33 /* Get the FPGA mode */
34 int fpgamgr_get_mode(void)
35 {
36 	unsigned long val;
37 
38 	val = readl(&fpgamgr_regs->stat);
39 	return val & FPGAMGRREGS_STAT_MODE_MASK;
40 }
41 
42 /* Check whether FPGA is ready to be accessed */
43 int fpgamgr_test_fpga_ready(void)
44 {
45 	/* Check for init done signal */
46 	if (!is_fpgamgr_initdone_high())
47 		return 0;
48 
49 	/* Check again to avoid false glitches */
50 	if (!is_fpgamgr_initdone_high())
51 		return 0;
52 
53 	if (fpgamgr_get_mode() != FPGAMGRREGS_MODE_USERMODE)
54 		return 0;
55 
56 	return 1;
57 }
58 
59 /* Poll until FPGA is ready to be accessed or timeout occurred */
60 int fpgamgr_poll_fpga_ready(void)
61 {
62 	unsigned long i;
63 
64 	/* If FPGA is blank, wait till WD invoke warm reset */
65 	for (i = 0; i < FPGA_TIMEOUT_CNT; i++) {
66 		/* check for init done signal */
67 		if (!is_fpgamgr_initdone_high())
68 			continue;
69 		/* check again to avoid false glitches */
70 		if (!is_fpgamgr_initdone_high())
71 			continue;
72 		return 1;
73 	}
74 
75 	return 0;
76 }
77